Physically fit young adults have healthier white matter in their brains
nytimes.com
nytimes.com
My personal opinion is that the 2 best things you can do to improve your own intelligence are to constantly challenge yourself to keep learning, and to exercise daily.
More info: https://www.mayoclinic.org/diseases-conditions/depression/in... https://www.alz.org/alzheimers-dementia/research_progress/pr...
I'm not convinced that it has. Lifestyle interventions in general tend to be given a lot of hype based on very little hard evidence, probably because lifestyle advice is unregulated and appeals to our biases about cultivating virtue. Of those I'm motivated enough to dig into, claims of lifestyle changes having a large effect on disease tend to be based on at least one of:
1) unfounded assumptions about the significance of a correlation (e.g. since exercise intolerance is a symptom of several cardiovascular and neurological conditions, it may be that getting less exercise is an effect rather than a cause of such a disease)
2) cherry-picking poor-quality or pilot studies
3) exaggerating the practical importance of a well-established but small effect
4) assuming that an intervention proven to improve X in a healthy population must help prevent or treat a disease that involves lowered or impaired X
For depression in particular, the effect of physical activity per se virtually vanishes in more rigorous studies, or when comparing leisure to non-leisure physical activity [1] [2]. Basically, the psychosocial meaning of "exercise", and the social structure surrounding it as a positive activity, seems to matter more than the actual exercise.
[1] https://www.cochrane.org/CD004366/DEPRESSN_exercise-for-depr...
"Dr. Repple says he and his colleagues are planning experiments to test whether and how various exercise programs affect fitness and the brain in people of different ages."
The reported study just documented correlations, so it gives no indication whatsoever on whether there are any causal effects at all.
For millions of years, the evolutionary winners of the human race were able to cognitively and physically outperform others. It makes intuitive sense that peak health has an “entourage effect” on other areas of the body.
In my own experience, when I've been out of shape, I felt that I wasn't living to my own expectation and felt some drive to improve. The exercise that followed seemed to improve my thinking too, so there was a bit of an upward cycle.
What you’re interested in is the treatment effect of doing sports vs not doing sports. With enough and the right kind of data you could try to estimate this effect while accounting for the potential endogeneity. Randomized experiments are a good way of generating such data, but even then the inference is tricky (subjects will know whether they are in the treatment or control group,...).
It is crazy though to see how many e-sports players are actually insanely muscular. I think it is most obvious in csgo where you have so many guys who are actually on forms of steriods and could probably compete at a strongman or bodybuilding competition. It is also one of the esports that is most aim and reaction time intensive, so that may be a reason it is like that.
The challenge for some people is how to be physically fit, or how to fit that activity into their own lives or within their own limitations. But surely any activity is better than none. And limit caloric intake to reasonable levels, which will make fitness easier for anyone.